


The Beat of Butterfly Wings

by writingwithmolls



Category: Fire Emblem Series, Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Character Study, Crimson Flower Route, F/F, Hurt/Comfort, Implied/Referenced Sex, Multi, Panic Attacks, Polyamory
Language: English
Status: Completed
Published: 2020-12-10
Updated: 2020-12-10
Packaged: 2021-03-10 04:36:22
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,496
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27998379
Author URL: https://archiveofourown.org/users/writingwithmolls/pseuds/writingwithmolls
Summary: According to Edelgard, a heartbeat isn’t something one thinks about.The body regulates it, some part of the brain telling the heart that it’s time to flutter, it’s time to pump the blood. Her heart terrifies Byleth the first time she hears it.OrByleth learns what it is like to have a heartbeat, but can only accept it with Edelgard and Dorothea helping her through the motions.
Relationships: Dorothea Arnault/Edelgard von Hresvelg, Dorothea Arnault/Edelgard von Hresvelg/My Unit | Byleth, Dorothea Arnault/My Unit | Byleth, Edelgard von Hresvelg/My Unit | Byleth
Comments: 10
Kudos: 68





	The Beat of Butterfly Wings

**Author's Note:**

> Just a warning that some of Byleth's symptoms are consistent with panic attacks, and there is implied sexual content.
> 
> Enjoy!

The average human heart beats 60 to 100 times in a minute.

Some have a lower resting heartbeat, the body accustomed to physical activity, but most dwell within the range. Even there, it differs from person to person, the heart beating and helping the body work its way through life. The heart beats and pushes the blood through a person’s arteries, beating faster when a loved one is near, and stays with one until their final breath. A heartbeat is a companion through life.

In some unusual cases, a person does not need a heartbeat to live.

It should have been medically impossible, but Byleth’s blood had always flowed without that essential part of the body. It pulsed through and brought life to her, but her heart never uttered a sound, never called out to the rest of its whole that it was alive. Sewn—melded—to it lay a crest who’s power replaced the meager human method of living.

Eagles flap their wings 20 to 80 times in a minute. When observed, they rarely do the flapping at all, they don’t need to. They mostly soar. Under a watchful eye, they will beat their wings that 20 times… keeping themselves stable in the sky. It’s a conscious movement, knowing that they must press themselves against the air in order to continue to propel forward.

According to Edelgard, a heartbeat isn’t something one thinks about.

The body regulates it, some part of the brain telling the heart that it’s time to flutter, it’s time to pump the blood. Her heart terrifies Byleth the first time she hears it.

It happened on a night that was restless. Byleth returned to the monastery after five years and Edelgard could not sleep, but for once it was not due to the terrors that haunted her in the nights. The excitement in her chest had been too much to contain and she knew that her teacher needed to rest, but she visited her anyway. The monastery was silent and Byleth could not sleep either, so they talked. They talked as the moon watched over them, the stars and their reverence protecting the time that they had missed.

Byleth had finally lay back in the bed, her head resting on Edelgard’s chest as the woman ran fingers through her green hair. Everything was calm for a moment until Byleth heard a persistent slamming noise coming from the emperor. It was quiet, yet violent all the same as it tickled her ears.

Edelgard, of course, had laughed when Byleth had asked about it, only realizing that she was serious when the professor frowned and held her fingers up to her chest, trying to find the source of the noise.

A heartbeat.

Byleth had thought for over two decades that the “beat” part was purely a phrase that was used to describe what was happening inside of the body. She didn’t know that there was supposed to be a persistent rhythm—like the sound of a drum—rattling in a person. Byleth didn’t know how to comfort Edelgard as her face turned as white as a sheet, her fingers and ears trying to find any source of life from the one she loved.

Byleth learned quickly that most people had that oddity, that sound, that gentle beat in their body. They told Dorothea, the woman laughing as if it was the funniest joke before placing her palm flat against Byleth and finding nothing. Even still, it was a secret that they kept between the three of them. It had never bothered Byleth before, so there was no reason to worry about the anomaly. Trying to unpack it always led to more questions than answers, so they let it be.

Dorothea had mentioned at one point that it was just strange that Byleth had never noticed. Even if she didn’t have a heartbeat of her own, how had she gone for so long without ever feeling someone else’s fluttering against her own self?

Byleth had never held anyone as close as she had Edelgard and Dorothea.

It was a harsh truth, but one that was soft all the same. Byleth became hypnotized by how their hearts functioned, how they quickened and pounded when she got close and kissed their lips. She loved the rest of their body’s reactions as well: the way their pupils dilated when they saw her, the red of their cheeks when her compliments reached their ears, how warm their bodies became when she touched them. She wanted to learn every bit of them, every reaction she could draw, every sigh and moan that they had to offer. Even so, she loved their heartbeats the most. 

Byleth didn’t expect that  _ having  _ a heartbeat would be so painful.

The first few times that it used all its strength to beat on its own, Byleth felt a surge of panic as it seemed to echo throughout her whole body. The world was on fire around them and the war was still roaring, but Edelgard held her tight. She passed out at that point, the emperor with tears on her face, a rare sight.

In the medbay, she would scream out those first few days when she was conscious, the overwhelming sensation of something  _ wrong _ flowing through her veins. Manuela would attempt to talk her through it, but often Byleth found herself gripped in the panic of the situation. Manuela would count the beats through with her, holding her stethoscope up to her heart for a minute. Usually the counts would lead to 72 beats per minute. It was normal, she promised, she just had to get used to it.

After a week of barley being able to keep her eyes open, Byleth didn’t sleep for the entirety of the next. During the day, she was beginning to learn how to ignore the beating, ignore the pulses that seemed to rattle her brain. Her former students would visit her in her quarters, joking with her that she regained something in that final battle. Their grand stories and reports were enough to distract her.

At night, with nothing but her own thoughts, the beat shook her very soul.

Butterflies, she learned, flap their wings 5 to 12 times a second… coming to about 300 to 720 times a minute. The news from Dorothea worried her, especially considering how she could barely keep control of her 72. How did the little creatures continue on knowing that they had to repeat the same movement, the same beat, ten times as much as Byleth’s own heart and brain struggled on? Dorothea promised that they didn’t even notice, it was natural to keep themselves in the air, to want to continue to fly. Soon enough, her own butterfly heart would learn to do the same.

How was she expected to live with such a burden?

The second week with her heartbeat had been terrible. She had stayed awake, curled in a ball and clutching at the tightness and moving in her chest as if it could still. Byleth didn’t sleep until her body finally relented and gave out, even her dreams haunted by the drumming. Manuela pitied her and gave her herbs to help her sleep, just enough that the exhaustion wouldn’t let the panic grate on her body any more than it already had.

The only thing that kept her tethered to the ground was Dorothea and Edelgard. After they had healed enough themselves, they gathered each night in Byleth’s room and held her between them. Gentle reminders that she would survive, she would grow used to the erratic beat, she would live on with them.

Dorthea would trace circles and hearts on the bare skin of her chest, reminding her to exhale whenever she held her breath for too long. Edelgard would keep her fingers gentle in her hair, brushing it out to the same steady beat, the same pattern that Byleth could relax into. Byleth always loved their heartbeats, and in the night they would take turns counting them out. The differences were small, none of their hearts functioned at the same rate, but they were all breathing, living. Sometimes Dorothea would fall asleep before her, but Edelgard would always keep her motions steady until Byleth gave herself over to the night.

Edelgard brought with her facts of beats, of how fast or slow the universe cycled around them. One of Byleth’s favorites was that hummingbirds manage anywhere from 53 to 80 beats a second with their wings. Their little hearts beat 1,260 times in a minute.

How could they manage an organ beating seventeen and a half times faster than Byleth’s own heart rate? It brought her comfort. If such a tiny creature could handle a fluttering pace, she would be able to take ownership of her own.

Slowly, but surely, Byleth let her heartbeat become a part of her person. A rhythm that Edelgard and Dorothea loved as much as she loved theirs. 


End file.
